An optical disk is a data storage medium which is readable by a laser-based reading device. Optical disks known as "compact disks" or "CDs" have become increasingly popular during the past few years for recording music and audio-video works. Due to the huge storage capacity of optical disks as compared to conventional magnetic storage media, optical disks known as "ROM disks" have become popular for storing computer readable information. However, until very recently, optical disks were of somewhat limited use in the computer industry due to the fact that optical disks could not be "erased" and "written" with new information, i.e. ROM disks are "read only" memory devices. However, recently, magneto-optical disks and other types of optical disks have been developed which are both computer readable and computer writable. Thus, in the future, optical disks are expected to become increasingly more important in the computer industry and may eventually replace magnetically readable and writable storage media such as "floppy disks" and "hard disks." Another recent development, the ability to provide data storage on both surfaces of an optical disk, has effectively doubled the optical disk storage capacity.
Optical disks of the type used in computer applications are mounted in a generally parallelepiped-shaped cartridge. Such a cartridge has a forward end which is generally provided with a ribbed surface portion which is adapted to be grasped between the thumb and index finger of an operator for handling the cartridge. The cartridge is adapted to be readably mounted in a conventional optical disk drive by grasping its forward end and inserting the cartridge, rear-end-first, through a narrow slot provided on the front face of a disk drive.
Currently, most optical disks are hand-inserted into disk drives. However, for large databases consisting of many optical disks, it is preferable, and perhaps essential, to provide an optical disk storage system for storing the disks at known locations, and an optical disk handling system which is capable of retrieving a desired disk from a storage location and inserting the disk in an optical disk drive. In a disk storage system wherein stored disks and an associated disk drive are positioned in longitudinally extending storage locations arranged in a two-dimensional array consisting of vertically extending columns and horizontally extending rows, it will generally be necessary for a disk handling system to engage and move each disk longitudinally, vertically, laterally, and, again, longitudinally in order to remove it from storage, move it into aligned relationship with a disk drive, and insert it into a disk drive. It may also be necessary for the disk handling system to flip the disk to reverse the side thereof which will be positioned in readable relationship with a drive.
An optical disk handling apparatus which is adapted to engage and longitudinally displace and/or flip optical disk cartridges for inserting and removing the cartridges from various storage locations of an optical disk storage system is described in U.S. Pat. No. 4,998,232 issued Mar. 5, 1991 of Methlie, Oliver, Stavely, and Wanger, which is hereby specifically incorporated by reference for all that is disclosed therein. Such devices are generally referred to in the industry as "autochangers" or "optical disk juke boxes".
Other optical disk handling devices and components thereof are shown and described in U.S. patent application Ser. No. 08/491,538 of Paul and Smith for DOOR ASSEMBLY FOR A CARTRIDGE HANDLING DEVICE, filed on the same day as this application and in U.S. patent application Ser. No. 08/491,440 of Schmidtke, Coffin and Christie for TENSIONING DEVICE FOR A FLEXIBLE DRIVE MEMBER, filed on the same day as this application, which are hereby specifically incorporated by reference for all that is disclosed therein.
A problem is encountered when loading cartridges into an optical disk handling and storage system which uses a handling apparatus such as disclosed in the Methlie et al. patent application referred to above.
The problem is that in order for a cartridge to be positioned in proper relationship for engagement by the handling apparatus, it must be presented with its forward end located adjacent to an engagement portion of the handling apparatus. In order to achieve such an orientation, it would appear necessary to pass each cartridge through a system housing in an orientation opposite to the orientation of the cartridge when it is inserted into a disk drive. In other words, it would seem that the cartridge must be passed through the housing forward-end-first rather than rear-end-first. The problem with inserting a cartridge into a housing forward-end-first is that it is unnatural and annoying for most operators. Further, damage to cartridges and/or jamming of the handling system may occur if cartridges are inserted in the wrong orientation.
This problem has been overcome by a device which rotates the cartridge 180 degrees, thereby allowing a user to insert a cartridge into the housing rear-end-first and yet still provide proper orientation within the system. This device is described in U.S. Pat. No. 5,062,093 issued Oct. 29, 1991 of Christie, Wanger, Dauner, Jones and Domal, which is hereby specifically incorporated by reference for all that is disclosed therein.
Some optical disk handling systems are provided with windows that allow an operator to view the optical disk handling apparatus within the system. Such windows have been found to be useful because they allow an operator to visually verify that the system is functioning and that it is functioning in a desired manner. Because of the configuration of most handling systems, these windows are usually placed in a 90 degree orientation with respect to the direction in which the handling apparatus removes disks from the optical disk insertion apparatus.
One disadvantage of the 180 degree system described in U.S. Pat. No. 5,062,093 referenced above, is that the window must generally be located on a surface of the system that is positioned 90 degrees from the user interface surface where a disk is inserted by an operator. It would be desirable to locate both the user interface area and the viewing window on the same surface so that an operator could access both without the need to walk around the system housing.
Another disadvantage of the system described in U.S. Pat. No. 5,062,093 is that the optical disk insertion apparatus is powered by the mechanized handling device. Although this eliminates the need for an additional transfer device drive motor, it also necessitates that the handling device sit idle while a user is loading or unloading a disk from the transfer device. Machine efficiency would be enhanced by allowing the handling device to function independently of the transfer device.
It has also been found that users occasionally improperly insert disks into optical disk insertion devices. This may occur when a disk is placed in the device backwards or when it is not fully inserted into the device.
Thus, it would be generally desirable to provide an apparatus which overcomes these problems associated with loading an optical disk cartridge into an optical disk cartridge handling and storage system. Similar loading problems may be encountered with other types of media autochangers in which the media is provided in a cartridge-type casing, for example floppy disks, removable hard disks and tapes.